Distributed XQuery processing techniques for realizing XQuery processing by using a distributed system have been developed. However, attempts to realize distributed XQuery processing have just begun, and it is only possible to find some documents written about distributed XQuery processing.
XQuery Remote Procedure Call (XRPC), which is a type of distributed XQuery Processing, is a language extension of XQuery for different types of distributed data sources. XRPC realizes distributed XQuery with a technical feature called Remote Procedure Call (RPC) used as a built-in function for an XQuery.